The benign baseline

In Module 2, you built a mental library of normal dermoscopic appearances. That library is your first tool when assessing any lesion.

Certain benign lesions have dermoscopic patterns so characteristic that they can be identified with high confidence:

• Seborrhoeic keratosis — milia-like cysts and comedo-like openings appearing together, fissures and ridges, sharp demarcation (Module 4)
• Cherry angioma — red lacunae with pale septa, homogeneous red pattern (Module 5)
• Dermatofibroma — central white scar-like patch with peripheral pigment network (Module 6)
• Common naevus — regular network, symmetric structure, one to two colours, gradual fading at the edges
• Solar lentigo — uniform brown colour, moth-eaten borders, fingerprint-like pattern on sun-damaged skin

When a lesion shows unequivocal features of one of these patterns, you can feel confident placing it in the "clearly benign" bucket. Modules 4, 5, and 6 will give you the depth to do this reliably for the three most common benign lesions.

But what happens when the pattern does not fit? That is what this module is about.